Pneumatic cleaning apparatus.



0. A. SCHLESINGER.

PNEUMATIC CLEANING APPARATUS. APPLICATION FILED DEC. 28, 1909.

LNMfiM. Patented May 23,1916.

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0. A. SCHLESINGER PNEUMATIC CLEANING APPARATUS.

APPLICATION FILED DEC. 28, I909.

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0. A. SCHLESINGER.

PNEUMATIC CLEANING APPARATUS.

APPLICATION FILED DEC. 28. I909.

Patented May 23,1916.

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OSCAR ANDRE-SEN SCI-ILESINGER, oFOAKLANlm cALIFORNIA, ASSIGNOR T0 VACUUM SPECIALTY MANUFACTURING COMPANY, A CORPORATION OF ARIZONA.

rnnunrn'rlc cnmmne APPARATUS.

Specification of Letters i atenti I Patented May 23, 191%.

Application filed. December 28, 1909. Serial No. 585,271.

To all whom it may concern Be it known that 1, 080m ANDRESEN Sonnnsmcnn, 'a citizen of the United States,

residing at- Oakland, in the county of Alameda'and State of California,.have invented a new and useful Pneumatic Cleaning Apparatus, of which the following is a specification in suchfull and clear terms as will enable those skilled in the art to construct and use the same;

This inventionrelates to a vacuum cleaner,

' and its .object is to produce a higher vacuum than is ordinarily possible with a free-running fan. In the art of vacuum cleaning, it is customary to use either free-running fans of the centrifugal type, or some formof a positively operating pump for small powers; the positively operating pump is not advantageous for the reason that itmust' be operated at a considerable speed, and its operation causes considerable vibration of the cleaning machine. also has the disadvantage that its weight cannot be reduced lowenough to be readily carried from place to place.

chine, showing the relation of the fans and motor. Fig. 3 is a plan view of themachine casing, with the top and one of the fans removed,-showing.the eight stationary vanes. Fig. 4 is a plan view of one of the fans. Fig. 5 is a sectional view of oneof the fans; and Fig. 6 is a plan view of the complete machine.

The numeral 1' represents the base of the machine, which may be of any desired form, said base having rubber feet 2'to prevent injury to polished floors. This base 1 supports the motor M, which has a vertical shaft 3. This vertical shaft is provided with two substantially identical fans or impellers 4 and 5 which comprise opposite upper and Y lower Walls arranged transversely to the v shaft and connected by a series of radial blades forming confined chambers; covering the motor, and fans, is a casing 6, having an opening immediately over the center'of plate 18.

Such a machine On the other, 'hand, the small single fan does not produce theupper fan, and having a packing joint around its upper corner at 8. This casing is. secured to the base by means of set screws 7.- Between the two fans there is placed a diaphragm 6, which is secured to the'casing 6 by means-of-the screws 10,

l which secure the hooks 10 in place on the casing 6. The diaphragm .6 is provided with a central aperture 21 and carries a series of vanes20 screwed'thereto which are curved at their outer ends. The object of these vanes is to deliver the air to the secondary fan with as little shock and with as littleeddying as possible. Each fan com-' prises a'flatdisk 15, provided with a head 16, tobe secured to the motor shaft, a series of vanes or blades 17 and a coned cover The vanes or blades are wider near the inlet of the coned cover plate than at their outer ends, so that the cross-sectional area upon any are of the impellerchanibers' may be substantially the same, thereby preventing any expansion of the air traversing the impellers and thus maintaining a maximum velocity of the air currents, and the conical cover plate is curved downwardly at its outer edge to direct the air to the delivery vanes with as'little loss due to eddying and friction against the side walls of the casing as possible. This construction of the impeller causes the air ejected from the elongated peripheral slot 19, of the upper impeller, to be directed downward substantially parallel to or concentric with the axis of the impeller, the rotary motion causing thestreams of air to strike the outer concave portions of the vanes 20, which direct it toward the central aperture 21 of the diaphragm 6, this action being greatly enhanced by the strong pull of the lower impeller 4, causing a constant suction or draft through the eye 4*.

In portable pneumatic apparatus it is of importance that the parts shall cooperate to produce the greatest efiiciency possible and that the losses shall be reduced to a minimum, by reason of the fact that the weight, space, and power must be kept very small indeed. It will therefore be observed that I place the inlet opening or eye 4, of the impellers 'as near as possible to the diaphragms, leaving only enough clearance for proper operation. Again, the conical upper wall of the impeller, by slanting toward the lower wall 15, not only forms a wedgeshaped contour, which oliers a small amount of resistance while rotating in a substantially closed space, but said slanting upper wall directs the air gradually toward the peripheral slot 19. This construction 'mabers extend transversely upon increasing arcs.

The value of these features will'be appreciated by engineers and others skilled in this art.

.The upper portion of the machine is formed of a dome 9 which is secured to the casing 6 by'means of hooks 10.. This dome is provided with an inlet head 11 having a glass 12 for observing the conditionyof the dust-laden air driven into the machine, a

handle 13, and an inlet pipe 14. This dome is ordinarily made of spun metal, but it may be made of any desired material.

The result of this construction is that one fan is forcing air into the other, whereby the vacuum produced may be very considerably increased. Experiments madeshow that one fan with a one-eighth-horse-power motor will produce a vacuum of about six inches of water, while with the two fans and the same motor, under precisely the same conditions, a vacuum of about eleven and one-half inches of water may be produced.

The motor has suitable lead wires 24 connected therewith, which extend outside the casing for connection to a suitable source of current supply. Any desired form of dustcollecting apparatus maybe placed 'in the dome 9, but thisinvention relates to the fan construction, and no claim is made to the dust-collecting apparatus. p

The operation of the machine is, as follows: A tool 25jhaving a hose 26 is connected with the pipe 14:. A suitable dustcollecting sack, not shown, is placed within the dome 9, and connected to the'inlet head in such a manner as to cause all of the air to-pass through the dust-collecting device. The -'motor is then started and the tool placed over the surface to be cleaned. The

. air is then drawn into thetool through the dome 9, into the fan5, along the delivery vanes into the fan 4, and out of the casing 5 at the bottom. r

Having thus described 'my invention,

. what I claim as new and desire to secure by 'Letters Patent of the United States, is as follows: 1. In combination in" a pneumatic clean- 1n apparatus-a casing, aplurality of impe lers rotatably mounted therein, eachim pellercomprismg a disk-shaped base plate;

a conical cover having a central openlngv or I eye, and a series of radial bladesconnecting said base plate and said cover, the periphery .aperture in alinement with an of said cover projecting beyond said base phragm. over each impeller lying in the same plane throughout its extent and having a central aperture in alinement with and in close juxtaposition to the eye of the adjacent impeller, a series of radial blades fixed upon the upper side of the lower diaphragm 'and having their upper longitudinal edges spaced from the lower side of the adjacent impeller base-plate to thereby reduce the friction upon said plate.

2. In combination'in a pneumatic clean-- ing apparatus a casing, and a plurality of impellers rotatably mounted thereln, each impeller comprising a disk-shaped baseplate, a diaphragm above each impeller having a central opening, a conical cover having a central opening or eye concentric with .said diaphragm opening, and a-series of radial blades connecting said base-plate and said cover, the periphery of said cover projecting beyond sa1d base-plate and curving downwardly to form a narrowvperipheral slot arranged to direct the ejected air downward substantially parallel to the impeller axis, and a series of radial blades .fixed upon the upper side of the lower diaphragm and having their upper longitudinal edges spaced from the lower side of the adjacent impeller base-plate to thereby reduce the friction upon the lower side 0 said base-plate. I

3. In combination in a pneumatic cleaning apparatus a casing, a plurality of impellers rotatably mounted therein, each impeller comprising adisk-shaped base plate, a conical cover having a central opening or eye, and a series of radial blades connecting said base plate and said cover, the periphery of said cover projecting beyond said base plate and curving downwardly to form a narrow peripheral slot arranged to 'direct the ejected air. downward substantially parallel with the im eller axis, a diaphragm over each impeller ying in the same plane throughout its extent and havin a central in close juxtaposition to the eye of the adjacent impeller, and a series of radial vanes secured to the intermediate diaphragm between two impellers and arranged to direct the air e ected from the peripheral slot of an upper impeller to the eye in the adjacent lower impeller, said vanes having their upper longitudinal ed es spaced from the lower side of the impe ler base-plate to thereby deciiease the frictional resistance upon said p ate.

4. In combination in a pneumatic clean- I ing apparatus a casing, and a plurality of impellers rotatably mounted therein, each impeller comprising a disk-shaped baseplate, a conical cover having a central opening or eye, and a series of radial blades connecting said base-plate and said cover, the periphery of said cover projecting beyond said base-plate and curving downwardly to form a narrow peripheral slot arranged to direct the ejected air downward substantially parallel with the impeller axis, a diaphragm located above each impeller having a central opening in alinement with the eye of said cover and lying in the same plane throughout its extent, said diaphragm being closely adjacent the cover at the center but increasingly spaced therefrom radially to thereby decrease the frictional resistance Y upon the top of the impeller, and a series of radial blades fixed upon the upper side of the lower diaphragm and having their upper longitudinal edges spaced from the lower side of the adjacent impeller baseplate to thereby reduce the friction upon the lower side of said base-plate.

In testimony whereof I have hereunto set my hand this 18th day of Dec, A. D. 1909, in the presence of the two subscribed witnesses.

OSCAR ANDRESEN SOHLESINGER.

Witnesses:

' O. P. GRIFFIN,

CHARLES R. HoL'roN. 

